Self-locking pulley



(NoModeL) .J. T. BURR. SELF LOCKING PULLEY.

Patented Oct. 13,1891

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I UNITED STATES PATENT OFFICE.

JESSE T. BURR, OF MOUNT VERNON, OHIO.

SELF-LOCKING PU LLEY.

SPECIFICATION forming part of Letters Patent No. 461,316, dated October13,1891.v

Application filed June 6, 1891. Serial No. 395,293. (No model.)

To all whom it may concern.-

Be it known that I, JESSE T. BURR, a citizen of the United States ofAmerica, residing at Mount Vernon, in the county of Knox and State ofOhio, have invented certain new and useful Improvements in Self-LockingPulleys; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the .art to which it appertains to make and use thesame,referencebeinghad to theaccompanying drawings, and to letters ofreference marked thereon, which form a part of this specification.

This invention relates to improvements in self-locking pulleys.

The object of the invention is to provide a device which willautomatically lock the hoisting-rope when the free end of the same islet loose; and my invention consists in the construction and combinationof the parts, as will be hereinafter fully set forth, and particularlypointed out in the claims.

In the accompanying drawings, forming part of this specification, Figurel is a sectional view showing the parts of the block in a position forhoisting, and Fig. 2 is a side view showing the rope locked.

A refers to the pulley-block, at the upper end of which is located theusual hook ct. To the lower end of the block is secured a pin b, towhich are pivoted brackets B B, said brackets being located on each sideof the' block and braced to each other by transverse pins or pivots, thecentral pivot c passing through enlarged apertures in the sides of theblock. The upper portion of the block is made solid, as at D, anddepending therefrom are the side Walls E E, between which and upon thepivot 0, carried by the brackets, is positioned the sheave G, over whichthe hoisting-rope passes. The inner wall d of the solid portion of theblock is preferably 'roughened,.so that when the hoisting-rope comes incontact therewith it will be better gripped. One end of thehoisting-rope K is secured to a swivel 6, located at one end of therock-frame, and passes through a pulley F and then up over the sheave Gand the roller H, located at the opposite end of the rock-frame from theswivel e. A rope or cord I may be secured in any suitable manner to theend of the rock-frame, where the roller H is mounted, so that therock-frame can be held in the position shown in Fig. 1 of the drawingsin lowering the load, which is attached to the pulley F.

With a block and tackle thus constructed, it will be understood thatwhen the free end of the hoisting-rope is drawn upon the rockframe willbe brought to the position shown in Fig. 1, so that the. load may beelevated, and by simply releasing the free end of the rope therock-frame will be swung upon its pivotb to clamp the rope between thesheave G and solid portion of the block, so as to sustain the load inany position.

I am aware that prior to my invention it has been proposed to provide ablock and tackle with sheaves, which are mounted upon rock-bars, so thatone of said'sheaves can be brought in contact with arms or a solidportion attached to the frame; and I therefore do not claim suchconstruction, broadly, as my invention.

lVhat I claim as new and desire to secure by Letters Patent, is'

1. In a self-locking pulley, the combination of a block A, havingcentral apertures O C .and a solid portion above said apertures, a

end of the frame opposite the guide-roller,

block and provided with a swivel e and roller In testimony whereof Iaffix my signature H at opposite ends thereof, and a sheave G, presence0f two witnessesl j ournaled centrally within the frame and positionedbetween the depending walls of the 5 block A, said block having a solidportion, WVitnesses:

which is roughened adjacent to the sheave, FRED BEAVERSORN,substantially as set forth. SOLON DAVIS.

JESSE T. BURR.

